Months ago I took notice to article news about Earth having limited amounts of fresh water, and decreasing amounts useable by people and in cities of vast population. So I decided to try doing my part of water conservation. I added a shut off valve to my shower head so I could turn it off as I wash and reenable it to wash off. I've also noticed it lowered my water bill a bit, so I assume it helps 2 fold, 1 being financially for me, and 1 for the Earth and other inhabitants. I hope others can adopt this mind set and help ourselves and others as well. And the parts cost less than $5-10 with about 10-15 minutes time. Don't forget to use Teflon tape aka plumbers tape or plumbers putty.